Switch operating mechanism with positive kickoff



Dec. 12, 1950 w. L. DIETRICH ,5

SWITCH OPERATING MECHANISM WITH POSITIVE KICKOFF 2 Sheets-Sheet 1 FiledNov. 4, 1948 INVENTOR WALTER L. DIETRICH 7? al- M ZiZZ/rne 5' Dec. 12,1950 w. 1.. DlETRlCH 2,534,007

SWITCH OPERATING MECHANISM WITH POSITIVE KICKOFF Filed Nov. 4, 1948 2Sheets-Sheet 2 TRANSIENT POSlTlQN INVENTOR WALTER L. DIETRICH 5y hisaZZ'ar-neys MMM.

Patented Dec. 12, 1950 UNITED STATES lPATENT 'SWITCH OPERATING MECHANISMWITH POSITIVE KICKOFF OFFICE Application November at, 1943, Serial No.58AM;

'7 Glairns. 1

This invention relates to electric switch operating mechanism. Moreparticularly the invention relates to a mechanism which operates with asnap action and in which the driven shaft or spindle is positively movedor kicked-off during movement of the switch to off position.

It is an object of the invention to provide an improved snap-actingswitch mechanism in which the operating shaft and handle when movingfrom one position of rest toward its next position, e. g.from on to off,will not move through an angle as great as the angle between thosepositions prior to operation of the switch mechanism. In other words,the handle and its shaft do not overtravel or travel past their nextposition when turned to operate the switch.

Another object is to provide a positive kickoff to start the actuatedelement or switch spindle on its way when the operating shaft has movedthe mechanism to dead center position.

Another object is to provide means to prevent removal of the handleshaft except when the switch is in off position, in a mechanism of theforegoing type.

Other objects and advantages of the invention will become apparent as itis described in connection with the accompanying drawing.

In the drawings:

Fig. 1 is an elevation view of a switch to which the operating and klCkOfi mechanisms are applied.

Fig. 2 is a plan view partly broken away of the parts of the inventionillustrated in Fig. l with the cover plate removed.

Fig. 3 is a transverse section view taken along I line 33 of Fig. 1illustrating the operating and kiclooff mechanism of the invention.

Fig. i is a view similar to Fig. 3 but with the parts in the positionwherein the kiclooff mechanism is functioning.

Fig. 5 is a fragmentary plan view of the central portion of the capplate in association with the operating stud shaft.

Fig. 6 is a fragmentary vertical section view of the operating shaft,handle shaft and cap plate of the switch.

Referring to the drawings, the body iii of the switch is mounted upon ametallic base plate l2 and has on its top a plate it. As illustrated theswitch body may be made up of a stack of insulating discs which aresuitably hollowed out to receive the contact-carrying elements bothfixed and movable of the switch.

The operating mechanism of the switch is mounted on the top plate It andbetween it and a mounting plate it. The mounting plate i6 is parallel tothe top plate Hi and is secured in place by nuts H which are screwed onthe ends of bolts ii passing through all elements of the switch body andextending beyond the top of the mounting plate it. By this means allparts of the switch body and associated plates are secured together. Themounting plate It may be spaced from the top plate M by a circularinsulating member preferably moulded from insulating material with acircular cavity in its center to permit movement of the operating partsof the switch-operating mechanism.

Rotatably mounted in the top plate M and in the base plate .12 is acontact-carrying spindle 20. The upper end 2! of this spindle isrectangular in section and extends slightly above the top plate M andhas mounted upon it a stamped sheet metal arm 22. A rectangular aperturein arm 22 receives the end 2! of spindle 20 and the end of the spindleis peened over on the arm so that the two turn as a unit. A pin 2extends from the outer end of arm 22 in the opposite direction from thespindle 2t and affords an anchor for one end of a tensioned over-centercoil spring 26. By the action of this spring, as will hereinafter bemore fully described, the arm 22 is moved between two fixed stop pins 23and mounted in the plate M and extending in a direction opposite to thespindle 2G. The stop pins 2% and 3B are so placed as to halt the arm 22and spindle 28 when the movable contacts, not shown, which are mountedthereon, are in register with fixed contacts of the switch (not shown).Since the fixed and movable contacts form no part of the invention andsince their structure may be varied widely within the scope of theinvention, they need not be described in detail. It is suilicient tomention that the movable contact may be a bridging contact which isinsulated in any conventional fashion from the spindle and turnstherewith so as to bridge the fixed contacts or disengage them accordingto the operation of the switch spindle.

Mounted in the middle of the mounting plate is an operating or studshaft, designated generally by the numeral iii in axial alignment withthe spindle Formed on the central portion of the shaft so is a collar 42which rests upon the upper surface of the mounting plate 16. The lowerend of the shaft ie extends through the mounting plate and its tip it isof reduced diameter and has flattened sides for the purpose of securinga stamped sheet metal operating lever 46 thereon. In one end :of lever46 is an aperture 3 in the course of actuation of to the position ofFig. 2 (oif) it i that the kick-off member 69 is of non-circular formconfigured to fit exactly around the tip 44 of the shaft 40 and the tip44 is peened over to permanently secure the operating lever andoperating shaft together for operation as a unit. The other end of theoperating lever 46 has a pin 48 mounted thereon and extending parallelto the axis of the switch spindle in direction towards the arm 22. Thispin 48 affords an anchor for the other end of the switchoperating spring26.

From the foregoing it may be seen that as the operating lever 46 ismoved in a clockwise direction from the position of Fig. 2 to theposition of r Fig. 3, the switch spring 26 will be stressed and its lineof action will pass across the coinciding axes of the spindle andoperating shaft thereupon causing the arm 22 and the switch spindle tomove in a counter-clockwise direction (referring to Figs. 2, 3 and 4)until the arm 22 strikes the stop 23.

As the operating leverliii is moved in the opposite (counter-clockwisedirection) the switch spring will again be caused to move across theaxis of the switch spindle and operating shaft to thereupon causereverse movement of the arm 22.

In order to stop the motion of the operating lever 46, pins 5!] and 52are mounted in the mounting plate l6 in a direction to extend toward thetop plate I4.

In order to positively move the arm 22 and switch spindle so as tocompel disengagement of the fixed and movable contacts in casetheyshould be inclined to stick, I have provided a kick-off member Gil,the main portion of which is stamped fiat from sheet metal but has anend '62 offset downwardly. The shape of the kick-off member may beobserved from examination of Figs. 1, 3 and 4. The kick-off member ispivotally mounted at one end upon a fixed pivot pin 64 extendingdownwardly from the under-side of the mounting plate iii. The kick-offmember 66 lies against the under-surface of the mounting plate l6 andhas a stud 56 extending downwardly from its mid-portion in position tobe engaged by the operating lever as as that'arm approaches dead centerposition in moving from on to off position of the mechanism.

The free oifset end 62 of the kick-off member when in the on position ofthe switch lies against the spring-anchor pin 24 of the contactoperatingarm 22 as may be observed by referring to Fig 3.

As may be seen in Fig. 4 when the operating lever 46 engages the stud t6the kick-off lever will be rotated in clockwise direction (referring toFig. 4) and by this rotation the offset end 62 will push the pin 24 andarm 22 in clockwise direction to start the spindle and the switchcontacts it carries moving in clockwise direction toward off position.Thereafter the'tension of the switch continues and completes themovement of the arm 22.

From the foregoing it may be observed that the location of the stops 28and 3B define and limit the angle of movement of the switch contacts andspindle 29; and stop pins 56, 52 define and limit the angle of movementof the operating lever 46 and stud shaft 40.

By referring to Fig. 4. into which the parts have been moved from the onposition of Fig. the mechanism may be observed positively engag- 4 ingthe arm 22 to move it. At this stage the operating lever 46 has movedthrough an angle substantially less than the full angle between Fig.3and Fig. 2. At the position of Fig. 4 or very slightly beyond thesnap-over of the arm 22 will take place. Hence'the operating lever 48and stud shaft 49 have no overtravel but cause actuation of themechanism prior to completion of movement on to off. Similarly,overtravel from off to on does not take place. Although the positiveoperating means does not function during the movement from off to onposition, there is no necessity for such positive movement since whenthe movable contacts are coming into engagement with the fixed contacts,they are already moving rapidly under the impetus of the switch spring.Thus normally and naturally any tendency of the contacts to stick whilethey are becoming engaged is overcome.

For'the purpose of manually turning the op erating stud shaft (it, itsupper end is slotted diametrically and is recessed axially by acylindrical bore 25. The cylindrical bore receives the end of anoperatin handle shaft it. A diametrical pin '52 is driven through thehandle shaft it and engages in the slot 4! in the stud shaft 49. Thehandle shaft 16 is therefore separable from the operating stud shaft 48.

Overlying the operating mechanism is a stamped metal cap plate 39 whichis secured in position by nuts 82 threaded on the ends of bolts 84 whichserve to mount the whole switch base and operating mechanism. The cap isap proximately circular in plan having a central portion pressed-out oroffset upwardly. In the center of the offset part of the cap plate 8c isan aperture aligned with the stud shaft 48, the aperture being of suchsize as to permit entrance of the end of the handle shaft "ill. .Sincethe handle shaft is provided with the diametrical pin 72, there isprovided a diametrical slot 88 communicating with the aperture 88 so asto permit entrance of the handle shaft it! but only when the pin i2 isin slot 88.

In assembling the cover on the switch, the slot 88 is so located withrelation to the slot M in the stud shaft 45} that the two are inregister register with the diametrical in the off position of theswitch. Upon insertion of the handle shaft and turning it to operate theswitch, the pin 72 will move immediately under the surface of the capBil. Thus in the on position of the switch and at all positions betweenit and off position, it will be impossible to remove the handle shaft.

Normally the handle shaft is mounted on and swings with a cover of theconventional box or housing which encloses the Whole switch mechanism. Asuitable mounting of the handle shaft on the cover is disclosed in myco-pending application, S. N. 49,260. Thus in view of the aforesaidcooperation of handle shaft and cap plate 80, it is impossible to openthe cover except in off position of the switch.

Many modifications within the scope of my invention will occur to thoseskilled in the art and therefore it is not limited to the specificembodiment illustrated.

I claim:

1. In an electric switch, a switch casing, a rotary spindle foroperating switch contacts within said casing, an arm mounted on saidspindle and turning therewith, an operating shaft in alignment with saidspindle but spaced therefrom, an operating lever mounted on said shaftand turning therewith, an over-center spring having its end connected tosaid spindle arm and said operating lever and movable by said operatinglever to cause movement of said switch spindle with a snap motion, akick-off lever pivoted about a fixed pivot spaced from the spindle axisand engageable by said operating lever when the latter has partiallymoved from one position of rest to another, said kick-oh lever engagingsaid spindle arm when the former has been engaged by said operatinglever whereby to positively start said spindle rotating, said springthereafter completing the rotation of said spindle from one switchposition to another, cover means cooperating with said casing to enclosethe aforesaid elements and having an opening for an end Of saidoperating member, a removable member engageable with said operatingmember through said opening, and means associ ated with said removablemember and said operating member to prevent removal of the former exceptwhen the spindle is in a certain position.

2. An electric switch as claimed in claim 1 wherein the connectionbetween said operating member and said removable member is a pin andslot connection.

3. An electric switch as claimed in claim 1 wherein there is a pin onthe removable member and a slot in said covering means to receive saidpin when said removable member is in a certain position and to preventremoval in any other position.

4. An electric switch as claimed in claim 3 in which the operatingmember is recessed to receive said removable member and pin.

5. In an electric switch, a rotary spindle for operating switchcontacts, means carried by and rotating with said spindle, a rotaryoperating means, spring means connecting said spindlecarried means andsaid operating means for moving the former when the latter has moved apredetermined distance, kick-01f means caused to engage with thespindle-carried means by said operating means when the latter has moveda predetermined distance whereby to positively start said spindlerotating, said kick-off means being pivoted about a fixed pivot spacedfrom the axis of said spindle, base and cover means cooperating to housethe aforesaid elements, said cover means having an opening for saidoperating means, a removable member engageable with said operatingmeans, and means associated with said removable member and saidoperating means to prevent removal of the removable member except whenthe spindle is in a certain position.

6. An electric switch as claimed in claim 5 wherein there is a pin andslot connection between said operating means and said removable member.

'7. In an electric switch, a rotary spindle for operating switchcontacts, means carried by and rotating with said spindle, a rotaryoperating means, spring means conecting said spindlecarried means andsaid operating means for moving the former when the latter has moved apredetermined distance, kick-off means caused to engage with thespindle-carried means by said operating means when the latter has moveda predetermined distance whereby to positively start said spindlerotating, said kick-off means being pivoted about a fixed pivot spacedfrom the axis of said spindle, base and cover means cooperating to housethe aforesaid elements, said cover means having an opening for saidoperating means, a removable member engageable with said operatingmeans, a pin on the removable member and a slot in said covering meansto receive said pin when said removable member is in a certain positionand to prevent removal in any other position.

WALTER L. DIETRICI-I.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 741,268 OBrien Oct. 13, 19031,499,139 Arnold et a1 June 214, 1924: 1,517,638 Kellner Dec, 2, 1924;

